The invention relates to a device for checking the soundness of the cigarettes in a packeting machine and, in particular, to a checking device suitable to be mounted on an infeed hopper of a cigarette packeting machine in order to detect and reject any faulty cigarettes before packeting.
In U.S. Pat. No. 3,520,394 in the name of the same Applicant as herein, a description is given of a hopper for the containment of a mass of cigarettes, the lower part of which is divided up into the same number of branches or elementary hoppers as there are layers of cigarettes (generally three) in one complete batch to be packeted.
Each elementary hopper is, in turn, partitioned with strips or baffles to form channels of a roominess approximately greater than the diameter of one cigarette, the number of these corresponding to the number of cigarettes (normally six or seven) that constitute one layer.
Layers of juxtaposed cigarettes are thus formed in the region of the bottom or outlet mouth of each of the elementary hoppers, and are fed, one layer at a time, into the pockets of an endless, intermittently moving, conveyor.
Through superposition, the layers gradually become, in the inside of the pockets, complete batches that the inching conveyor transfers to wrapping means.
In accordance with what is known and described, for example in U.S. Pat. No. 3,771,279 in the name of the same Applicant as herein, means for checking the soundness of the cigarettes are provided in the region of the channels or, alternatively, along the path followed by the endless conveyor.
The checking means can, for example, be of electro-mechanical type and comprise sensor means constituted by feeler pins which, by axially stressing the extremities of the cigarettes, check the degree of filling thereof.
The result of the checking operation is then sent, through a memory device, to means for ejecting batches wherein there are one or more faulty cigarettes, placed along the path followed by the endless, intermittently moving, conveyor.
The checking and ejecting system, though advantageous from a practical viewpoint, is decidedly uneconomical since a complete batch of cigarettes is expelled because of just one faulty cigarette.